Pediatric AIDS is a growing concern, particularly in the inner city areas served by the members of our team. Recent surveys have demonstrated an alarming rise in the number of pregnant women with evidence of HIV infection and a consequent rise in the number of HIV-infected infants. This application proposes to expand our AIDS Clinical Trials Unit to conduct pediatric studies related to HIV infection. These studies will encompass all stages of therapeutic evaluation and drug development: Phase 1 (pharmacokinetic/safety studies), phase 2 (continuing safety/initial efficacy studies), and phase 3 (definitive efficacy studies). Our unit has been a member of the AIDS Treatment Unit program and has developed a consortium of hospitals and investigators with the capability to develop protocols, to recruit patients with HIV infection, coordinate data and specimen collection, perform virologic and immunologic evaluations, as well as pharmacokinetic studies, maintain quality control of laboratory results and data entry, develop protocols, and collaborate with NIAID and the other institutions involved in adult trials. To this existing organization will be added pediatricians, pediatric research nurses, social workers and additional laboratory, administrative and support personnel. The proposed studies will be conducted at hospitals serving two of the highest AIDS incidence areas in the country - East Harlem and Manhattan's lower east side, as well as Elmhurst, Queens, an area with a high proportion of immigrants from areas of the world where AIDS is transmitted heterosexually. The combined obstetrics services at the participating hospitals estimate 75 to 100 deliveries per year to HIV infected mothers. An additional important resource is our hemophilia program. Well designed controlled clinical trials are essential if we are to improve our ability to treat children with HIV infection.